Since a ball bearing has a good operating performance, which includes a high load, a low frictional resistance, a small rotational deflection, and a high rigidity, a high-speed rotating system generally uses the ball bearing as a support member for supporting a rotating shaft. This can prevent high-speed rotation of the high-speed rotating system from causing temperature rise and friction loss issues.
With the rapid development of related industries such as the machinery industry or the aviation industry, one of the current trends in industrial development includes promotion of the rotational speed of the rotating shaft and improvement of the working efficiency of the rotating system. Moreover, with the development of mechanical processing technology, the precision requirements of the rotating shaft have gradually increased, so that the high-speed performance and the precision of the ball bearing need to be improved for achieving the requirements of the rotational speed and precision of the mechanical rotating shaft.
The high-speed performance and precision of the ball bearing are not only affected by the material and machining precision of the ball bearing, but also affected by the structure of the ball bearing. A typical ball bearing includes an outer ring, an inner ring, a plurality of balls, and a ball retainer. The ball retainer is used to separate the balls from each other, so that the balls can be arranged on ball tracks between the inner ring and the outer ring and spaced apart from each other, and each two of the balls arranged adjacent to each other have the same angle with respect to the central axis. The ball retainer is approximately in an annular shape and includes a plurality of pocket holes that are in an annular arrangement for receiving the balls, and each two of the pocket holes arranged adjacent to each other have the same angle with respect to an axis and are spaced apart from each other. In order to allow the balls to be rollable in the pocket holes of the ball retainer, and a diameter of each of the pocket holes of the ball retainer needs to be larger than an outer diameter of the corresponding ball. However, a gap will exist between each of the pocket holes of the ball retainer and the corresponding ball. Accordingly, when the ball bearing is in operation, the ball retainer and the balls can still be movable relative to each other.
Generally, the conventional ball retainer has two guiding modes. One of the two guiding modes is a steel ball guiding mode, which usually does not consider that the ball bearing is prone to deflect and interfere with the balls under a high-speed operation. The other guiding mode is an outer ring guiding mode, and can be used to stabilize, balance, and reduce the deflection under a high-speed operation. However, the ball retainer of the outer ring guiding mode will brush against the outer ring under a low speed operation so that the ball bearing in each of the two guiding modes is met with increased resistance during operation and generates additional vibrations, affecting the stability and precision of the ball bearing operation.